curl --location --request POST 'https://demo.myshopify.com//admin/api//carrier_services.json'
{
"carrier_service": {
"id": 1036894957,
"name": "Shipping Rate Provider",
"active": true,
"service_discovery": true,
"carrier_service_type": "api",
"admin_graphql_api_id": "gid://shopify/DeliveryCarrierService/1036894957",
"format": "json",
"callback_url": "http://shipping.example.com/"
}
}